Rebuilt 727 shifts but no downshift

[hoover]

I rebuilt my first 727 this past winter, finally got it in and did the test drive.
The kickdown linkage is correct, and adjusted properly.
I added a tf2 shiftkit while i was cleaning the valvebody, I am wondering if there is something that I could have assembled backwards or wrong that would cause this?

 

[493 Mike]

I rebuilt my first 727 this past winter, finally got it in and did the test drive.
The kickdown linkage is correct, and adjusted properly.
I added a tf2 shiftkit while i was cleaning the valvebody, I am wondering if there is something that I could have assembled backwards or wrong that would cause this?

Can you clarify the operation with more detail? It does up shift automatically? Can it be down shifted manually? It does not down shift at all?
Mike

 

[hoover]

It upshifts automatically, and will manually downshift.

 

[dvw]

Does the throttle pressure linkage have the spring holding it forward to the carb stud?
Doug

 

[hoover]

Yes, it all worked well before the trans started to slip.
As far as I know it had never been rebuilt before.

 

[Dave6T4]

At rest, the kickdown lever MUST be fully forward, or pressure will be retained in the governor circuit, not allowing transmission to shift back at stops, etc. As dvw said, make sure return spring is hooked up.

 

[hoover]

Everything is hooked up

 

[zombezoo]

At rest, the kickdown lever MUST be fully forward, or pressure will be retained in the governor circuit, not allowing⁸ transmission to shift back at stops, etc. As dvw said, make sure return spring is hooked up.

So I will qualify this with I am not an expert but I experienced something similar with my rebuilt 727.
I had a spring pulling the kickdown lever fully forward at idle and the trans would shift quickly into 3rd at all throttle positions and would not kick down at all once I was over 30mph. I found I had to adjust my kickdown cable tighter to keep some level movement dialed in at idle. This caused my part throttle shift points to go higher and allowed for part throttle upshifts.
I'm running a lokar style cable setup.
There's more to it than just having full level action at full throttle like many of the guides say.
What is your carb and kickdown setup on this vehicle? All factory parts? Anything aftermarket?

 

[hoover]

It's a cast iron dual quad itake on a 505 in my 67 rt.
Factory linkage that i modified to work with the 2x4s.
It all woked fine until the old junkyard transmission gave up,which I expected to happen with this engine.

 

[zombezoo]

It's a cast iron dual quad itake on a 505 in my 67 rt.
Factory linkage that i modified to work with the 2x4s.
It all woked fine until the old junkyard transmission gave up,which I expected to happen with this engine.

If it worked before then I would expect it would work now. Your probably right chasing internal issues.

 

[451Mopar]

Look at the shift kit instructions for how the throttle valve / spring assembly goes into the valve body, and also the gap between the throttle valve and lever stop.

 

[Geoff 2]

Make sure thew governor is working. It detects the speed reduction & need to downshift.

 

[The Rebel]

I'm by no means an expert but have you checked the fluid level?

Does the kickdown spring provide the correct tension?

 

[hoover]

On the governor- I cleaned that and installed higher upshift weights.
The fluid level looks to be good with it in neutral and hot.
Maybe the next step is to pull the VB and check it over.

One thing to add; the shifts are not nearly as firm as I expected.
I put the car on my lift and re checked that the KD lever was at the end of it's travel with the carburetors at WOT.
That is good, and the return spring is doing it's job.
Thanks for all of the input!

 

[dvw]

I should have clarified this before my first post. When you say no downshift. Does this mean no forced full throttle downshift with hard throttle? Or does it stay in high gear after coming to a stop? If it's no forced downshift take a pressure reading at the accumultor port. While running at idle manually move the the lever back (disconnected from the carb). Should be around 50 psi idle lever forward. Close to 100 psi with the lever back. I had a valve body last year that did this. It had a crack in the throttle valve wall limiting full pressure. If the pressure is low there is a problem in the valve body. If it sticks in high gear check governor pressure. It must return to zero with the driveshaft not turning. If it doesn't return to zero the governor is sticking. The tech at Trans Go is very good. After pressure checks I would call them.
Doug

 

[hoover]

It goes back to low gear when stopped, then shifts to 2, and 3.
No downshift when i stand on the pedal.

 

[icetech]

It goes back to low gear when stopped, then shifts to 2, and 3.
No downshift when i stand on the pedal.

Hope you figure it out, mine does the same thing but i am not in the mood to worry bout it for now. TF-2 kit in mine also.. pretty sure i missed something.

 

[RJ Squirrel]

You did not mention what year the trans is, if it does not have ptkd get a newer valve body (71-up?) that has PTKD in it (part throttle kick down) and put your shift kit in that.

 

[hoover]

The trans is out of a 78 new yorker.
If i figure this out I will share what the cause is.